Weight Loss Wales at Obesity Week 2026: Seasonal Variation in Weight Management Outcomes

Today, 13 November 2026, Dr Alun Davies of Weight Loss Wales is presenting three original research posters at Obesity Week 2026 in Washington DC — the world's largest obesity medicine conference, hosted by The Obesity Society and the American Society for Metabolic and Bariatric Surgery. This is the first of three posts covering each poster.

Why seasonal variation matters in obesity medicine

Weight management is not a linear process. Patients, clinicians, and researchers have long observed that weight loss trajectories are not uniform across the calendar year — that certain times of year are associated with greater difficulty maintaining progress, higher rates of treatment disengagement, and increased risk of weight regain. Yet until now, this clinical observation has rarely been examined rigorously using real-world data from a structured obesity service.

The first poster presented by Dr Davies at Obesity Week 2026 addresses this gap directly. Drawing on outcome data from Weight Loss Wales — the first Healthcare Inspectorate Wales-accredited fully remote obesity clinic in Wales — the analysis examines seasonal patterns in weight loss, weight regain, and patient engagement across the clinic's patient cohort.

What the data show

The analysis identifies clinically significant seasonal variation in patient outcomes. Consistent with clinical intuition, the data show that certain periods of the year — including the Christmas and New Year period and the summer holiday season — are associated with measurable changes in weight trajectory and treatment engagement. The findings are drawn from real patients receiving structured medical weight management through a fully digital, high-touch service model.

Importantly, the data also identify periods of heightened clinical opportunity — times of year when patients are most motivated and most likely to achieve significant progress. Understanding this seasonal landscape allows clinicians to time interventions more strategically, intensify support proactively during high-risk periods, and set more realistic expectations with patients about the natural rhythm of weight management.

Implications for clinical practice

The findings support the case for seasonally-aware obesity management protocols. Rather than treating all months of the year as equivalent, a seasonally-informed approach would:

• Schedule proactive check-ins and intensified support in the weeks before known high-risk periods
• Adjust weight loss targets and expectations to account for seasonal headwinds
• Use seasonal transitions — particularly January and September — as natural re-engagement points for patients who have drifted from their programme
• Incorporate seasonal awareness into patient education, normalising the experience of seasonal difficulty rather than framing it as personal failure

Why this research matters

Real-world data from structured obesity services are rare in the published literature. Most clinical trials are conducted under conditions that do not reflect the complexity of everyday obesity care — they exclude patients with multiple comorbidities, use highly controlled dietary protocols, and follow patients for fixed periods that rarely capture seasonal cycles. Data from a real-world remote clinic, treating a broad population of adults across Wales, offer a different and complementary perspective.

Presenting this work at Obesity Week 2026 — alongside researchers from the world's leading academic medical centres — reflects the quality and originality of the data generated by Weight Loss Wales, and the clinic's commitment to contributing to the evidence base that underpins obesity medicine globally.

The full poster is available to download from our Advice for Clinicians page. If you are a healthcare professional interested in our real-world outcome data or CPD training, please get in touch directly. If you are a patient considering medical weight management, book a consultation with Weight Loss Wales today.